Field of the Invention
Description of the Prior Art
A common water-saving sheet can lessen a water flow through decreasing a total cross-sectional area of a tube so as to save water.
However, when a hydraulic pressure is small, the conventional water-saving sheet still blocks the water flow and cannot adjust the water flow according to the hydraulic pressure. In addition, the water-saving sheet is fixed in the tube through abutting against the tube radially, and the water-saving sheet falls off easily.
US patent publication 2011/0247702 disclosed a water-saving sheet having a sealing ring covering the sheet. The sealing ring is made of resilient material to make the sheet abut the inner wall of the tube firmly. However, the elasticity is limited because it's completely provided by the resilience of the material.
U.S. Pat. No. 4,000,857 disclosed another water-saving sheet. The sheet is clamped by two tube units screwed with each other, so the sheet is firmly positioned. However, the sheet can not be used in a single tube structure.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.